1. Field of Invention
The embodiments of the invention relate in general to data packet traffic regulation in networks. More specifically, the embodiments of the invention relate to methods and systems for data packet regulation in network devices such as data switching systems and routers.
2. Description of the Background Art
The need to transfer data such as work files, audio files, etc., has increased exponentially in today's world. This has given rise to the concept of connecting data sources and data receivers such as computer workstations, data servers, etc., in a network such as a local area network (LAN), a wide area network (WAN), and the Internet. The data transfer between the data source and data receiver takes place with the help of a network device, which enables the data transfer. Data sources and data receivers are connected to the network device through communication channels. Examples of network devices include routers, switches and bridges.
When a user wants to send a data packet from a data source to a data receiver, the data packet transfer in a network device takes place in the following manner: The user sends the data packet from the data source to the network device, which then transfers the data packet to the relevant data receiver with the help of a data switch. A data switch can be a switching device such as a combined input output queue (CIOQ) switch or a virtual output queue (VOQ) switch and the like.
The network device has a communication channel, which has a particular capacity, to transfer data packets. Whenever there is congestion in the network device, data packets accumulate in the network device, which gets flooded with data packets. The data packets accumulate in a buffer provided in the network device, which accommodates these data packets before they are sent to the data packet receiver. However, if the number of accumulated data packets exceeds the capacity of the buffer, it leads to severe congestion in the network device. The flooding of data packets results in the formation of a data packet queue at the input and the output of the network device. The formation of a queue at the network device may hamper the smooth transfer of data packets in the network and result in delays and losses in the transmission of data packets. It also hampers the working of the network device.
Conventional techniques for reducing congestion include either dropping or suppressing the data packets in the event of congestion at the network device. The decision to drop, mark to indicate congestion, or suppress data packets can only be taken after measuring the queue length formed by the data packets at the network device.
However, the queue length is not an exact indication of the magnitude of the congestion in the case of a complex network with more than one input and output queue at the network device. Further, it is difficult to simultaneously measure the queue length of different queues. Consequently, measuring the congestion level accurately is difficult. Moreover, in this kind of mechanism, data packets are evenly distributed in the buffers, in the case of congestion, to maximize buffer utilization, which, in turn, hinders an accurate assessment of the extent of congestion in the network device. Further, the queue length is not an exact measure of the congestion level, to evaluate the variable rate of data transfer at the output ports of the network device.